I've had good luck with them. They are yellow, if color matters to you. Meaning the immediate visual cue of yellow primer = once fired does not apply - if you care.

To be honest, in 20+ years of reloading, I've never noticed any difference with performance, reliability, pressure, or velocity as a function of primer. With the exception that sometimes I see a minor velocity difference with magnum primer - sometimes.

That's what CCI recommends for 223.

Myself, I have never used them. I use Rem 7 1/2 and Wolf SRM.

Many here use CCI 41's and are quit happy with them.

I have no proof but suspect you are correct about the high primers.

The only place I have heard much of anything about rare slam fires is at service rifle matches . I believe the majority of shooters are useing reloaded
ammo. The general shooting population here at AR15 seems to shoot quite a bit when mom loans them the mini van to go to the range and the majority seems to use mostly factory ammo but you don't really hear of any slam fires.

I have certainally shot a bit of facvtory ammo but have yet to see a slam fire. My few reloads for rifle are only for matches but reload or factory I
am aware how the gun is pointed before the bolt is dropped

I have used them exclusively in my 25-223 loads, no issues what so ever.

I'd try a few in some of the non-AR15 guns. I have been using small rifle primers in pistol ammo for years now. I tried using some #41s in some 9mm. I'd never had any issues with any other small rifle primer prior to this. These wouldn't reliably ignite in a 1911. But what really surprised me was that it wouldn't reliably ignite in an Uzi SMG. I've got several hundred loaded that aren't much good. I keep thinking I should see if they will run in an AR15/9mm. If not, I guess I'll pull them apart and at least reuse the bullets.

Also, I did some accuracy testing with them and some other primers in an AR15 chambered in .300/221 (Noveske barrel, from before the 300BLK was released). The #41s showed much worse accuracy than the other primers. Everything else was the same re: bullets, powder, brass. Maybe not an issue for .223, but it's something to think about.

I've been meaning to try it with a few other types of primers. Someone suggested Rem 7-1/2s, but I can't find any locally. I literally just drove from one side of the state to the other and couldn't find any.

CCI 41's are GTG...I use them in my Grendel loads and for any .223 loads other than my plinking stuff. I'm getting low though and may switch to the Wolf magnum primers.